Predicting the postmortem interval using human intestinal microbiome data and random forest algorithm

Gradual changes in microbial communities in a human body after death can be used to determine postmortem interval (PMI). In this study, gut microflora samples were collected from the vermiform appendix and the transverse colon of human cadavers with PMIs between 5 and 192 h. The results revealed that the appendix might be an excellent intestinal sampling site and the appendix flora had an inferred succession rule during human body decomposition. Firmicutes, Bacteroidetes, and their respective subclasses showed a predictable succession rule in relative abundance over time. A Random Forest regression model was developed to correlate human gut microbiota with PMI. We believe that our findings have increased the knowledge of the composition and abundance of the gut microbiota in human corpses, and suggest that the use of the human appendix microbial succession may be a potential method for forensic estimation of the time of death.     

Estimate of the random match frequency of acquired characteristics in a forensic footwear database

When analyzing footwear impression evidence, a significant task of the forensic examiner is to determine if a questioned impression could have originated from a known shoe. To form this opinion, examiners typically evaluate the similarity, quantity, and quality of shared class characteristics and characteristics of use. Since these criteria are developed through training and experience, and therefore purported to be subjective in nature, the opinions formed regarding footwear evidence can be misunderstood. One way to mitigate this criticism is to complement casework with research that includes quantitative analyses. The aim of this study was to estimate random match frequency of randomly acquired characteristics (RAC-RMF) in a research database comprised of 1,300 outsoles with more than 80,000 RACs. Based on a combination of visual comparisons (>91,000) and mathematical predictions (>3.8 million), results indicate that 32% of the outsoles in this dataset do not share any indistinguishable RAC pairs with each other, while 19% possess RAC-RMFs of 1 out of 1,299. At the other extreme, the maximum RAC-RMF observed was 49 out of 1,299. These results are based on high-quality test impressions, human assessments, and a single quantitative similarity metric, so they are considered specific to this dataset and method of analysis. Results could differ in other databases and with impressions of lower quality, and therefore should not be extrapolated to casework. Despite this limitation, the results provide a point of reference for how often RACs may repeat in position and geometry on non-mated outsoles, therefore forming the basis for future research.     

建构主义学习理论大学英语教学设计和教学模式范式研究

建构主义学习理论既强调学习者的认知主体作用,又不忽视教师的指导作用。建构主义学习理论教学设计是与学生的学习环境相适应的全新的教学设计;与建构主义学习理论教学设计范式相适应的目前已开发出的、比较成熟的教学范式为：支架式教学、抛锚式教学和随机进入教学。     

Forest offences in 21st Century Turkey (with the example for the offender and trial period of illegal use of the forests in Istanbul)

Turkey's forests are under supervision and control of the state. The applicable Forestry Law decides which acts would be considered as forest offences and the punishment for them. In the study, the acts described as crimes have been explained by considering them within the framework of criminal law. Misdemeanors have been excluded and only crimes have been examined. Major forest offences have tried to be explained through statistical data and information related to perpetrators of the crime; the trial period and court judgments have been presented as a result of file observations in İstanbul. It has been observed that the increase in forest offences in Turkey changes depending on the country's economic structure and the changes in legislation. These offences have also been found to be in decline as of late. It can be stated that adjudications have been concluded more immediately. However, there are still doubts about the penalties' not being deterrent enough.     

Bioinformatics Approach to Assess the Biogeographical Patterns of Soil Communities: The Utility for Soil Provenance,

Soil DNA profiling has potential as a forensic tool to establish a link between soil collected at a crime scene and soil recovered from a suspect. However, a quantitative measure is needed to investigate the spatial/temporal variability across multiple scales prior to their application in forensic science. In this study, soil DNA profiles across Miami‐Dade, FL, were generated using length heterogeneity PCR to target four taxa. The objectives of this study were to (i) assess the biogeographical patterns of soils to determine whether soil biota is spatially correlated with geographic location and (ii) evaluate five machine learning algorithms for their predictive ability to recognize biotic patterns which could accurately classify soils at different spatial scales regardless of seasonal collection. Results demonstrate that soil communities have unique patterns and are spatially autocorrelated. Bioinformatic algorithms could accurately classify soils across all scales with Random Forest significantly outperforming all other algorithms regardless of spatial level.     

The effects of an experimental intensive juvenile probation program on self-reported delinquency and drug use

In the late 1990s Ventura County, California, USA, implemented the South Oxnard Challenge Project (SOCP), designed to provide intensive, multi-agency services to youth on probation. SOCP built their program guided by Clear’s “corrections of place” model, which argued that community corrections could decrease offender risk by focusing on restorative principles rather than on coercion. SOCP was designed as a randomized experiment, comparing youths in the experimental group with those on routine probation. Researchers interviewed youths in both the experimental and control groups 1 year after random assignment. This article reports on self-reported crime and drug use, finding few significant differences across groups. Specifically, we find that SOCP youths were significantly more likely to indicate that they had committed a violent crime generally, although a majority of both groups indicated they had done so. We found that those in SOCP who robbed people also did so significantly more often than did the comparison group. In the control group, youths reported committing homicide significantly more often, but this was a rare event. Among those youths who reported taking part in gang or posse fights, those in the control group did so significantly more often. Finally, youths in the control group were significantly more likely to have used ecstasy on more days during the previous month than were those in the SOCP.

Strengthening the citizens' role in international organizations

Today's international organizations are characterized by a fundamental deficit in democracy. We therefore propose institutional measures to increase the direct participation possibilities of the citizens in international organizations. In order to reduce the number of citizens involved in decision-making to a manageable size, a representative sample of trustees is selected using a random mechanism. The trustees are given the right to launch initiatives and to vote in referendums on issues related to an international organization's constitution. They can also recall executives when they are dissatisfied with their behavior. No specific changes to the organization of these entities, especially their executive function, are proposed. Rather, the executives of international organizations must obey the constitutional changes adopted by the trustees. The proposal gives international organizations democratic legitimacy. Moreover, the executives are subjected to the control of the citizens of the member states, which induces better responsiveness to the preferences of the people, as well as higher organizational efficiency. JEL codes D72 · 019     

预期不确定下的林权制度改革——陕西太白山区调查之二

在生态林为主地区所进行的林业产权制度改革会遇到什么问题?林农对林改的反应如何?陕西太白山区两个村庄的实际情况说明:第一,生态林政策的不确定带给林农的收益预期不确定,并导致了村民以规避风险为主要内容的选择;第二,在同样政策背景下,小农户更倾向于选择降低风险,而承包大户则可以为未来可能的收益增加投入;第三,由于存在多方利益的互动,在太白山区,以均权、均山和均利为特征的林权制度改革政策被演变为抽多补少,让每户都有一片维持生存的山林的政策;这种政策将会导致山林占有的差距被扩大,并被合法化。     

A Comparison of Methods for Analyzing Criminological Panel Data

We demonstrate that fixed- and random-effects models for pooled cross-sectional and time series data, and latent growth curve models for panel data are special cases of a more general model. We compare the estimates obtained from each type of model for a data set consisting of homicide rates and a vector of explanatory variables for 400 US counties over a 15-year period. Most, but not all, estimates are similar in the two models. We identify circumstances under which one approach may be advantageous to the other.

Random votes under compulsory voting: Evidence from Brazil

Compulsory voting is known for boosting electoral turnout, even when sanctions for abstaining are small or loosely enforced. Much less is known, however, about the consequences of compulsory voting on vote choice, and, in particular, about the quality of electoral decisions. In this paper, we explore the extent to which voters meaningfully engage in the electoral process or simply vote randomly because voting is required by law. We conducted a large online survey in Brazil during the 2018 national elections to assess if voters engage in random voting. We evaluate random voting for low-profile, low-information elected offices (state and federal legislators) and others that receive greater media coverage (governor and president) and evaluate the determinants of random voting for each of them. We find that: 1) random voting does not appear to be affected by social desirability bias; 2) there is substantial random voting under compulsory voting; 3) more voters tend to engage in random voting in low-profile, low-information elections, as compared to elections that receive greater media coverage; and, 4) interest in politics, education, and disposition to vote if voting were to be voluntary reduce random voting. Our findings carry important implications for the study of citizen participation and civic competence under compulsory voting and for democratic representation, more broadly.